Phonograph-record and method of making the same.



PATENTED OCT. 3, 1905.

'1. A. EDISON.

PHONOGRAPH RECORD AND METHOD OF MAKING THE SAME.

APPLICATION FILED JUNE 29.1904.

I 11 V6 11 t or iiW/MJA. Z (1280/0 Witnesses Attorney.

UNITED STATES PATENT oEEIoE.

THOMAS AfEDlSON, OF LLEWVELLYN PARK, NEl V JERSEY, ASSIGNOR TO NEWJERSEY PATENT COMPANY, OF ORANGE, NEW JERSEY, A COR- PORATION OF NElVJERSEY.

PHONOGRAPH-RECORD AND METHOD OF MAKING THE SAME.

Specification of Letters Patent.

Patented Oct. 3, 1905.

Application filed June 29, 1904. Serial No. 214,650.

To all whom, it may concern:

Be it known that I, TnoMAs A. EDISON, a citizen of the United States,residing at Llewellyn Park, Orange, county of Essex, and State of NewJersey, have invented a certain new and useful Improved PhonographRecord and Process of Making the Same, of which the following is adescription.

My invention relates, first, to an improved IO phonograph-record,whether of the cylinder or disk type, in which a plurality of independent record-grooves are formed in the recording-surface, whereby itbecomes possible to secure a plurality of phonographic repro- I 5ductions from the same record, and, second, to an improved process forproducing such records.

In an ordinary phonograph-record the available space in which therecordgroove may be formed is one one-hundredth of an inch in width, andin this space the very shallow record-groove is cut by a circularrecordingtool (actuated by the diaphragm) of about four one-hundredthsof an inch in diameter.

5 I find that by properly reducing the diameter of the recording-tool itbecomes practically possible to cut as deep a record-groove as that nowformed in a space whose width is only half or even one-quarter as greatas that now util- 3 ized, or from about one two-hundredths to onefour-hu ndredths of an inch. 1 am therefore enabled to form on arecord-surface two or more complete recordgrooves, any one of which maybe engagedby a proper reproducer-stylus of small diameter, so that areproduction from any record-groove can be secured. In this way withoutincreasing the size of the records and without changing thereproducing-machines, except to the extent of using a repro- 4ducer-stylus of reduced diameter, I am enabled to make use of multiplerecords with theobvious commercial advantages incident thereto. Theimproved process consists in cutting the plurality of record-grooves inthe recording material either simultaneously or successively, and itinvolves a preferred preliminary adjustment of the recording tool ortools in order that the records may not conflict or interfere with oneanother, but may be entirely 5 independent, so that the reproduc'erstylus may be engaged with any one of them throughout the entirereproduction. A record formed in this way can be used directly on areproducing-machine, or it may be obviously du plicated by any suitableprocess and any number of copies obtainedtherefrom, care being of courseobserved that the pitch of each record-groove shall correspond with thefeedscrew of the phonograph, so that the reproduction may be perfectthroughout.

In order that the invention may be better understood, attention isdirected to the accompanyingdrawings, forming a part of thisspecilication, and in which- Figure 1 is a side elevation, on anenlarged scale, of a cylindrical phonographic recor embodying my presentimprovements am showing the formation of two complete record groovesthereon greatly exaggerated; and Fig; 2, a detail elevation, on the samescale, of :1 part of this record, illustrating the process of making thesame.

In the views corresponding parts are represented by the same numeralsand letters of reference.

The duplex records are formed on a blank 1, which is of the usualrecording material. This blank is somewhat longer than those ordinarilyemployed, so as toprovide a clear space at the left of the line X X onwhich the proper adjustment may be secured. The recorder 2 is of smallerdiam ter than those ordinarily used, one of a diameter 0f- 020 of aninch being shown, with which a sufficiently deep record can be formed ina space only one twohundredths of an inch in width. Obviously byreducing the diameterof the recording-tool the depth of the record maybe increased. Preferably the recorder is engaged with the blank 1, whichis then rotated to form a smooth groove (0 in a space at the left of theline X X, and when this line is passed the recording-diaphragm will besubjected to the effect of sound-waves to form a complete record-groovea on the blank. 'Obviously between the record-groove so formed a blankspace will be left in which one or more record-grooves may be out. Afterthe record-groove (1 has been formed the recorder is again engaged withthe blank at the left of the line X X to form a smooth groove b. Theposition of this groove with respect to the groove (1 may be observedunder the microscope and the recorder adjusted until the groove Z1 islocated exactly between the groo\ a, so that when the line XX is passeda co blank.

more record-grooves are desired these operaplete record groove 7/ may becut in the It will be evident that if three or tions will becorrespondingly modified, necessitating, of course, the employment of a.smaller recording-tool. After the desired records are formed on theblank the latter is cut off at the line X X and may then be used in a.reproducing-machine, or it may be employed as a besecured. By makingtherecordsvery hard a small reproducing-stylus can be made use ofWithout undue wear.

While I prefer to form a record-groove in he way described by firstcutting one groove n the blank and then adjusting the recorder ind thencutting a second record-groove alternately arranged with respect to thefirst recordgroove, it will be understood that two or more diaphragmsmay be used actuating separate recording-tools, which diaphragms aresimultaneously subjected to the different soundvibrations, whereby allof the record-grooves may be formed simultaneously on the blanks.

Having now described my invention, what I claim as new therein, anddesire to secure by Letters Patent, is as follows:

1. Asanew article of manufacture, a soundrecord tablet carrying on itssurface a continuous sound-re ord extending around the axis of saidtablet a plurality of times and an independent sound record lyingbetween the windings of said first-named record and extending about theaxis of said tablet a plurality of times, substantially as set forth.

2. As a new article of manufacture, a cylindrical sound-record tabletcarrying on its surface a continuous sound record extending around theaxis of said tablet a plurality of times and an independent sound-recordlying between the windings of said first-named record and extendingabout the axis'of said tablet a plurality of times, substantially as setforth.

3. As a new article of manufacture, a soundrecord having an extendedportion carrying a plurality of continuous alternately-arranged groovesand on its main portion, a continuous extension of such grooves,alternately arranged representative of sound vibrations, substantiallyas set forth.

4. The process of making duplex sound-records which consists in cuttingin the face of a blank tablet a continuous sound-record groove extendingaround the axis of said tablet a plurality of times, and an independentsound-record groove between the windings of said firstnamedrecord-groove and extending about the axis of said tablet a plurality oftimes substantially as set forth.

5. The process of makingduplex sound-records which consists in cuttinginthe face of a blank cylindrical tablet a continuous soundrecord grooveextending around the axis of said tablet a plurality of times, and anindependent sound-record groove extending about the axis of said tableta plurality of times, substantially as set forth.

6. The process of making duplex sound-records, which consists incuttinga sound-record groove on a blank cylinder with a space betweenthe groove, and in then cutting one or more continuous sound-recordgrooves on the space presented between the first groove, substantiallyas set forth.

'7. The process of making duplex sound-records, which consists incutting a smooth groove on a blank cylinder, and in then subjecting thecutting-stylus to the action of sound-waves to cut a sound-record on thecylinder as a continuation of the smooth groove, then in adj usting therecorder to out a smooth groove on the blank in the space presentedbetween the first smooth groove, and finally in subjecting the recorderto sound-vibrations to cut a second sound-record on the blank in thespace presented between the first recordgroove,substantially as setforth.

This specification signed and witnessed this Q ith day of June, 1904.

THOS. A. EDISON.

\Vitnesses' FRANK L. DYER, ANNA R. KLEHM.

